We now know Tamerlan and Dzhokhar Tsarnaev, the two brothers said to be behind the Boston Marathon bombings, planned to head for New York City to detonate more improvised explosive devices. As it turns out, that plan was foiled by the quick thinking of one Mercedes-Benz owner, diligent police work and the Mercedes-Benz mbrace system. When the brothers carjacked a 26-year-old Chinese entrepreneur identified only as "Danny," they didn't realize his Mercedes-Benz M-Class was equipped with the mbrac